1. Field of the Invention
The present invention relates to a display apparatus. More particularly, the present invention relates to a display apparatus capable of improving display characteristics and a method thereof.
2. Description of the Related Art
In general, a display apparatus is an apparatus which displays an image by receiving an image signal. Such a display apparatus is classified as either a cathode ray tube (“CRT”) display, a liquid crystal display (“LCD”), an electrophoretic display (“EPD”), and the like.
The CRT display has a vacuum tube disposed therein, and an electron beam is irradiated from an electron gun to thereby display an image. Since the CRT display requires a sufficient amount of space to allow the electron beam to rotate, a thickness of the CRT display is large, and a weight of the CRT display is large.
The LCD is used to display an image using a characteristic in which an alignment direction of liquid crystals is altered due to an electric field. The EPD is used to display an image using a phenomenon that charged particles move due to an electric field, i.e., electrophoresis. The LCD and EPD are thinner and lighter than the CRT display. In particular, since the EPD is a reflective display that displays an image by using external light, an additional light source is not required. For this reason, the EPD is thinner and lighter than the LCD.
Each of the LCD and EPD includes an array substrate and a color filter substrate joined with the array substrate such that the array substrate and the color filter substrate face each other. The array substrate includes pixel electrodes arrayed in a matrix form and (“TFTs”) that switch data voltages applied to the pixel electrodes. The color filter substrate includes color pixels respectively corresponding to the pixel electrodes and a common electrode which faces the pixel electrodes. An electric field is formed between the array substrate and the color filter substrate due to a potential difference between the pixel electrodes and the common electrode.
Meanwhile, in the LCD and EPD, an intensity of the electric field is low in low-voltage driving, and thus a contrast ratio is also low. In particular, charged particles in the EPD do not move freely due to an occurrence of collisions between the charged particles. Therefore, the EPD has a lower contrast ratio than the LCD. For example, when displaying a predetermined color of a corresponding color pixel, other colors which neighbor the predetermined color may be displayed. That is, when displaying the color of a red pixel, the colors of green and blue pixels may be displayed, and thus a purity of the red color is degraded.
Meanwhile, since the respective red, green and blue pixels have different luminances and visibilities, an amount of each of the red, green and blue pixels must be adjusted in order to keep a white balance. To this end, thicknesses of the red, green and blue pixels are formed to be different from one another. However, a process of forming the thicknesses of the red, green and blue pixels to be different from one another is not easy, and a planarization of a color filter substrate is degraded due to the different thicknesses of the red, green and blue pixels.